Blog posts with problems to get your brain going! You get a new problem every fortnight and the solutions are published later.

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The next problem is scheduled for Sunday, 27th of June.

You may notice some problems are missing... I'm still migrating articles from my old blog.


Alice and Bob sit across each other, ready for their game of coins. Who will emerge victorious?


Can you find a really large triangle that is also really tiny?

You are sunbathing when you decide to go and talk to some friends under a nearby sun umbrella, but first you want to get your feet wet in the water. What is the most efficient way to do this?


I bet you have seen one of those Facebook publications where you have a grid and you have to count the number of squares the grid contains, and then you jump to the comment section and virtually no one agrees on what the correct answer should be... Let's settle this once and for all!


Take out a piece of paper and a pencil, I am going to ask you to write some letters in your sheet of paper and then I am going to challenge you to fold the sheet of paper... with a twist!


This post's format will be a bit different from the usual and the first of a series of posts of this type. In this post, I will state a problem and then present my solution.